Serious Eats - seriouseats.com

In high school, my boyfriend's dad was the head of the dairy science department at the university in my hometown, and he always said "sell by" or "best before" for dairy meant you can use it for about a week after the date. I definitely "follow my nose" with these things, as I hate wasting food. I've also read that it's okay to cut mold off of hard/semifirm cheeses, as long as you cut off 1/2" or so around the moldy spot...that's definitely something I did growing up as well...but you shouldn't do this with soft cheese, as mold spreads throughout them much more rapidly.

When I was a kid things like mustard and catsup didn't even have expiration dates. I pay no attention to most condiment dates. The same with canned goods, if the can isn't swelling, the inside of the can isn't showing signs of degradation and the food inside still smells and looks good, I'll eat it.

I'm pretty cautious with dairy, although an expiration date for cheese, especially hard cheeses or unopened packages, is just silly. You pay more for aged cheeses! Cream, sour or otherwise, usually lasts longer than the date, but non-fat milk usually doesn't make it TO the expiration date. It starts to taste "off" a couple of days early. Buttermilk seems to last forever.

Meats are a whole other thing. I pay close attention to the dates for meats. Even cured meats get eaten or frozen before the expiration date. Exception to that rule is the dry aging of good beef.

Haha none. Not after the time in college that I made a chinese chicken salad with dressing that had expired two years ago. My roommate and I were near death for a few days. You know how there are some items that stay good until you open them? Salad dressing is not one of them. :-)